Stair climbing wheel system



FIG. 1 is a perspective view of a stair climbing wheel system showing our new design;

FIG. 2 is a top view of the stair climbing wheel system, the bottom view, front side view, and rear view being identical to the top view, and thus are not shown; and,

FIG. 3 is a right side view of the stair climbing wheel system; the left side view being identical to the right side view and thus is not shown. 

The ornamental design for stair climbing wheel system, as shown and described. 